Stop mechanism fob knitting



Feb. 6, 1934. I WACHSMAN Re. 19,069

STOP MECHANISM FOR KNITTING MACHINES Original Filed Nov. 3, 1950ATTORNEY Reissued Feb. 6, 1934 UNITED STATES PATEN T OFFICE STOPMECHANISM FOR. KNITTING MACHINES Jacob Wachsman, Brooklyn, N. Y.

Original No. 1,835,732, dated December 8, 1931,

Serial No. 493,179, November 3, 1930.

cation for reissue November 9,1933. Serial Claims. (Cl. 66-163) duringthe normal operation of the knitting machine, the yarn keeps said leversin a circuit open position, but when a knot occurs in the yarn one ofsaid levers is moved to a circuit closing position and when the yarnbreaks, the other of said levers is moved to close the circuit. Theclosing of the circuit in either event operates; to stop the machine.

One object of my invention is to provide an electric stop mechanismwhich shall be of compact sturdy construction, eflicient in operationand economic to manufacture.

Another object is to provide a construction which admits ofmodifications and changes to suit the particular place and type ofknitting machine with which the stop mechanism is to be used, butwithout necessitating fundamental changes in the general construction.

Again, it is an object to provide a gravity actuated lever which willtend to lift the thread off the surface of the spring-held lever arms,there- 'by to reduce the areaof contact between the thread and theseparts, instead of having the gravity actuated lever press the threaddown on 0 the surface, of the spring-held lever arms as in priorstructures.

Further, it is an object to provide against the accidental closing ofthe circuit by a mere slacking of the thread.

Other objects will in part be obvious and in part be pointed outhereinafter.

To the attainment of the aforesaid objects and ends, the invention stillfurther resides in the novel details of construction, combination andarrangement of parts, all-of which will be first bodiment which has beenespecially designed for use with medium weight thread.

Figure 6 is a perspective view of a further embodiment which has beenespecially designed for use with a heavy thread. It is obvious however,that the statements as to the use of the difierent embodiments of theinvention are not intended fully described in the following detaileddescrip-' tion, then be particularly pointed out in the appended claims,reference being hadto the accompanying drawing, in which:-

Figure '1 is a side elevation of one embodiment of my invention whichhas been especially designed for use with fine thread, the electriccircuit of the stop motion mechanism being diagrammatically indicated.

Figure 2 is a front elevation of the device shown in Figure 1.

Figure 3 is a plan of the same.

Figure 4 is a vertical longitudinal section on the line 44 of Figure 3.I

Figure 5 is a perspective view of another emto be a distinctclassification with respect thereto.

In the drawing I provide a housing consisting. of a supporting plate 1having a bent over end 2 for mounting and provided with shoulders 3 toconstitute stops for limiting the movement of the spring-held lever 13hereinafter referred to. The plate 1 is also provided with a ut-awaypor- 7 tion 4.while the bent over or mounting portion 2 of the plateisprovided with a hole 5 for the reception of a screw or bolt 6 by meansof which the device may be mounted on a.- suitable supporting part ofthe knitting machine.

The housing also includes a box '7 whose front is closed by the plate 1and which is secured to that plate by screws or bolts 8. Mountedwithinthe box '7 is a long 'contact spring 9 and a short contact spring 10secured to a suitable terminal golt 11 that is mounted on, but insulatedfrom, the

Bearing notches 12 are provided in the side" Walls of the box 7 for thespring-held lever 13 whose parallel arms embrace the plate 1 and extendforwardly thereof, terminating in porcelain fingers 14 having concaveportions 15 to hold the thread T. The spring-held lever where it passesthrough the box 7 is provided with a heel 16 for effecting contact withthe springs 10 and 9 when the lever 13 is pulled down against thetension. of the hold-back spring 18 as will later be explained. Thespring 18 has one end hooked into a stirrup 17 that is carried by theheel 16 and it has its other end anchored to a screw 19 which carries anadjusting nut 19a whereby the tension of the spring may be regulated.

20 designates a gravity actuated lever which is mounted in suitablebearing notches 22 in the side walls of the box 7 and which has a looppor- 1 tionor heel 21 to engage the contact spring 9 when the lever 20is raised beyond a certain limitf as will later be more fully explained.

The lever 20 has a rearwardly extending portion 23 bent over to underliea pivoted weight-lever 24 which is also mounted. in suitable bearing,notches 25 in the side walls of the box 7 and which has for its purposeto over-balance the lever 20 and continuously tend to elevate it to aposition higher than that indicated'in dotted lines in Figure 1, wherebywhen so elevated to the highest position the heel 21 of thelever willengage the contact spring 9 and close the electric circuit.

The lever20 in the first embodiment of my invention has its front endbent into approximately. the shape of the letter Mv thus providing twoloops 26 with threeparallel rods 23 which lie between the porcelainfingers 14 of the springheld lever 13 when the, thread T is in position,

see Figure 1.

' 28 is the downwardly and forwardly inclined portion of a guard memberformed of wire and tions 2928 of the guard will pass within the loops 26between the parallel portions 27, it being understood that the verticalportions 30 continuously lie projected through the loops 26 and betweenthe fingers 14, see Figures 1 and 2.

The portion 31 of the guard which is anchored at '8 is continuedlaterally as an extension 32 to constitute a stop for limiting theupward movement of the gravity actuated lever 20. By bending theprojection 32 up or down (see Figure 29 the height to which the lever 20may be permitted .to rise before en aging the stop 32 may becorrespondingly varied;

In the embodiment of, my invention shown in Figure 6, those parts whichare of the same con-- struction as shown in Figure 1 bear the samereference numerals. Those parts which correspond in construction andfunction but are diflerent in form from the parts shown in Figure I bearthe same reference numerals plus the index letter 11. In this'embodiment(Figure 6) the back stop 33 is formed as a part of the gravity actuatedlever 20 instead of as a part of the guard as in In the embodiment shownin. Figure 5,those parts which are of the same construction ascorresponding parts in. Figure 1 bear the same reference numerals andthose parts which are of similar construction and perform the samefunction as corresponding parts in Figure 1, but differ therefrom inform, bear the same reference numerals plus the index character I. Inthe em- I bodiment of Figure 5 it will be observed that-the guard is asingle guard and'the gravity actuated lever has but a single loop 263:instead ofthe 'double guard and loop structure shown in Figure 1.

The electric stop mechanism which is controlled by my circuit closermaybe of the. ordinary construction, and as'it per se formsno part of the.present invention, it has been merely ditically indicated in Figure 1,by reference to which it will be observed that 34 is the battery and 35the magnet which actuates the stop motion actuating lever 36 to stop the*machine when the magnet is energized.

'In the. use of 'my invention the device is mounted ata'suitablelocation on the ,knitting machine and the thread is laid over the'twochine it is under suificient tension to hold gravity actuated lever insubstantially the positions indicated in Figures 1, 4, 5 and 6. Thegravity actuated lever being overbalanced by the weight-lever 24,continuously tends to' raise the threads so as to reduce its frictionalcontact area with the fingers 14 tending to assume the position shown inFigure.2 but normally not quite reaching that position. When, however,the thread slacks then the position shown in Figure 2 and in dottedlines in Figure 1 'will be reached, but the electric circuit will not beclosed in the box 7 because the guard 28 overlies the thread T andprevents the gravity actuated lever from raising to its circuit closedposition; However, as soon as the end of the thread passes the guard thelever 20 will rise and'close the circuit, thus stopping the movement ofthe knitting machine.

'Furthermore, if undue tension'is put upon the thread as for example ifa knot causing a stoppage of'the movement of the thread before itreaches thecircuit closer, the thread will pull down the levers 20 and13 and slip off of the same, thereby at once releasing both the levers13 and 20 and permitting them to close the electric -the circuit is notdependent upon the presence of the overhanging guard or the back stopwhich are simply additional devices for the sake of precaution. When aknot occurson'thethread, the spring lever will be pulled down to closethecircuit and when the threadbreaks or runs out the gravity operatedlever will be swung upward and also close the circuit and this willhappen irrespective of the guard or back stop.

From the foregoing description, taken in connection with theaccompanying drawing, it is thought the complete construction, operationand advantages of my invention be clear to those skilled in the art towhich it relates.. What I claim'is: s V 1. In stop mechanism undercontrol of a travelling thread, a circuit closer unit comprising ahousing, a fixed contact member insulated from and mounted in saidhousing, a circuit. terminal therefor, a spring-held lever fulcrumed insaid housing and including two substantially parallel arms extending tothe outside of said housing,

wardly beyond a predetermined position, said gravity actuated leverhaving its fore end-positionedto be held between said parallel arms bythe thread placed thereover, and overbalancing means continuouslytending to move said gravity actuated lever to bring its fore end abovesaid I arms and move it to a circuit closing position.

2. In stop mechanism under control of a travel- 'therefor, a spring-heldlever fulcrumed in said housing and including two substantially parallelarms extending to the outside of said housing, and having a contact heelto engage said contact memher when said arms are pulled down, a gravityactuated lever also fulcrumed in said housing and having a contact heelto engage said contact member when said gravity actuated lever ismovedupwardly beyond a predetermined position, said gravity actuated leverhaving its fore end positioned to be held between said parallel arms bythe thread placed thereover, and overbalancing means continuouslytending to move said gravity actuated lever to bring its fore end abovesaid arms and move it to a circuit closing position, and a guard membermounted on said housing to hold said gravity actuated lever againstclosing the circuit so long as a thread lies over the fore end of saidlever.

3. In stop mechanism under control of a travelling thread, a circuitcloser unit comprising a housing, a fixed contact member insulated fromand mounted in said housing, a circuit terminal therefor, a spring-heldlever fulcrumed in said housing and including two substantially parallelarms extending to the outside of said housing, and having a contact heelto engage said contact memher when said arms are pulled down, a gravity,arms and move it to a circuit closing position, and

a vertical back stop located between said arms. 4. In stop mechanismunder control of a travelling thread, a circuit closer unit comprising ahousing, a fixed contact member insulated from and mounted in saidhousing, a circuit terminal therefor, a spring-held lever fulcrumed insaid housing and including two substantially parallel arms extending tothe outside of said housing, and having a contact heel to engagesaid.contact member when said arms are pulled down, a gravity actuated leveralso fulcrumed in said housing and having a contact heel to engage saidcontact memher when said gravity actuated lever is moved upwardly beyonda. predetermined position, said gravity actuated leverhaving its foreend positioned to be held between said parallel arms by the threadplaced thereover, and overbalancing means continuously tending to movesaid gravity actuated lever to bring its fore end above said arms andmove it to a circuit closing position, and a guard member mounted onsaid housing to hold said gravity actuated lever against. closing thecircuit so long as a thread lies over the fore end of said lever, saidguard member also including an upright back stop located between saidarms.

5. In-stop mechanism under control of a travelling thread, a circuitcloser unit comprising a housing, a fixed contact member insulated fromand mounted in said housing, a circuit terminal. therefor, a.spring-held lever fulcrumed in said housing and including twosubstantially parallel arms extending to the outside of said housing,

and having a contact heel to engage said contact tion, said gravityactuated lever having its fore a finger on said gravity actuated leverto underlie said pivoted member.

6. In stop mechanism under control of a'travelling thread, a circuitcloser unit comprisinga housing, a fixed contact member insulated fromand mounted in said housing, a circuit terminal therefor, a spring-heldlever fulcrumed in said housing and including two substantially parallelarms extending to the outside of'said housing, and having a contact heelto engage said contact member when said arms are pulled down, a gravityactuated lever also fulcrumed in said housing and having a contact heelto engage said contact member when said gravity actuated lever is movedupwardly beyond a predetermined position, said gravity actuated leverhaving its fore end positioned to be held between said parallel arms bythe thread placed thereover, and overbalancing means continuouslytending to move said gravity actuated-lever to bring its fore end abovesaid arms and move it to a circuit closing position, and a guardmemberincluding a projection serving as a stop to limit the upwardmovement-of said gravity actuated lever.

'7. In stop mechanism under control of a travelling thread, a circuitcloser unit comprisinga housing, a fixed contact member insulated fromand mounted in said housing, a circuit terminal therefor, a spring-heldlever fulcrumed in said housing and including two substantially parallelarms extending to the outside of said housing, and having a contact heelto engage said contact member when said arms are pulled down, a gravityactuated lever also fulcrumed in said housing and having a contactheelto engage said contact member when said gravity actuated lever is movedupwardly beyond a. predetermined position, said gravity actuated leverhaving its fore end positioned to be held between said parallel arms bythe thread placed thereover, and overbalancing means continuouslytending to move said gravity actuated lever to bring its fore end abovesaid arms and move it to a circuit closing position, and a guard membermounted on said housing to hold said gravity actuated lever againstclosing the circuit so long as a thread lies over the fore end of saidlever, said gravity actuated lever having its fore part formed with aplurality of parallel portions adapted to becaused to lie between saidarms when a thread is in place, and said guard comprising portions tolie between each pair of said plurality of parallel portions, :saidguard member including a proiection serving as a stop to limit theupward movement of said gravity actuated lever.

B. In stop mechanism under control of a travelling thread, a circuitcloser unit comprising a housing, a fixed contact member insulated fromand secured in said housing, a circuit terminal therefor, a spring-heldlever fulcrumed in said housing and including a thread receiving portionextending to the outside of said housing and having a contact heel toengage said contact member when said lever is pulled down by the thread,a gravity actuated lever alsofulcrumed in said housing and having acontact heel to engage said contact member when said gravity actuatedlever is moved upwardly beyond a predetermined position when the threadbreaks, said gravity actuated lever having its fore end positionedunderneath and in contact .with the thread adjacent to the aforesaidthread receiving portion. a

9. In'stop mechanism under control of a travelling thread,'a circuitcloser unit comprising a.

housing, aflxed contact member insulated from and secured in saidhousing, a circuit terminal therefor a spring-held lever fulcrumed insaid.

housing and including a thread receiving portion extending to theoutside of said housing and having a contact heel to engage'said contactmember when said lever is pulled down, a gravity actuated lever alsofulcrumed in said housing and having a contact heel to engage saidcontact member when said gravity actuated lever is moved upwardly beyonda predetermined position, said gravity actuated lever having its toreend positioned to be held in a circuit open position underneath thethread adjacent to saidportion by the thread placed on the latter andoverbalancing means continuously tending to "move said gravityactuatcdlever to bringits fore end above the said spring-held lever andmove it to 'a circuit closing position.

10. In a stop mechanism under control of a travelling thread, a circuitcloser unit comprising a housing, a fixed contact member in'saidhousing, a lever piy'oted in the housing and having a thread receivingsubstantially straight portion extending away from the housing undermathand across the path of the travelling thread normally placed thereon, aspring for nor mally maintaining said lever with its thread receivingportion in a substantially horizontal posi- 4 tion in engagement withthe thread, a contact heelon said lever to engage said contact memberwhen said thread receiving portion is pulled down a slight distancebelow its. normal position, a

gravity actuated lever also pivoted in said hous-' ing and having asubstantially straight thread engaging fore end portion extending awayfrom the housing underneath and across the path of the travelling threadadjacent to said thread receiving portion, a contact heel on saidgravity actuated lever to engage said fixed contact member andoverbalancing means for operating said gravity actuated lever to acircuit closing position when the thread no longer is present on saidthreadreceiving portion.

a JACOB WACHSMAN.

